Imagine: You're at work and you start feeling sick, but instead of leaving and driving to your doctor, you head down the hall, to the medical facility.

A day after hurting her shoulder, Juanita Luna knew she needed a doctor. But instead of leaving work early for an appointment, she checked in with her company's health care center right down the hall. She was able to see the doctor five minutes later.

"I would have had to take off work, call my doctor. Probably would have resulted in about a half day out of the office," said Juanita Luna, PG&E employee.

Larry Boress is with the National Association of Worksite Health Centers. He says a recent survey finds a third of companies now offer some form of health services on site.

"Having an onsite clinic really gives them a great opportunity to quickly get to the service they need or pick up the drug or see the doctor or nurse and then get back to work," said Larry Boress, Worksite Health Centers.

Services can range from a single room where employees can check their vitals and Skype in to an on-call doctor, or to elaborate facilities like where Juanita works at PG&E, which can offer services ranging from acute care to acupuncture and even physical therapy.

A spokesperson for PG&E says the company listened to its employees and these are the services they asked for.

"We don't want them spending time traveling or waiting for health care. We want them to get the right healthcare at the right time," said Angela Lombardi, PG&E spokesperson.

And it can be less expensive too.

"People have less out-of-pocket costs because the clinic itself doesn't have to generate revenue," said Larry Boress, Worksite Health Centers.

These centers can also help employees stay healthy by offering nutrition and smoking cessation programs.